Swing-out manhole cover

Abstract

A swing-out manhole cover assembly having at least one ramp to facilitate opening and closing the cover. The manhole cover assembly includes a frame, a cover, a swing assembly and at least one ramp. As the cover swings open away from the frame about the swing assembly, the ramp imparts linear translation to the cover separating the cover from the frame slightly. As the cover swings back to close the manhole cover, the ramp reverses the linear translation and the cover returns back to the frame. A spring may be included to bias the cover in the closed position.

Description

RELATED APPLICATION[0001]The present application is a continuation-in-part of U.S. application Ser. No. 11 / 420,083, which was filed on May 24, 2006 (now U.S. Pat. No. 7,341,398).BACKGROUND OF THE INVENTION[0002]The present application relates to manhole covers, and, more particularly, to a swing-out manhole cover.[0003]Manhole covers are well-known and widely utilized. Generally, a manhole cover provides access for maintenance of infrastructure, for instance wiring or piping. Traditional manhole cover assemblies include a frame that is attached to the substructure housing infrastructure to be maintained. Examples of such substructure include the base for a road or sidewalk. The manhole cover may be locked for security or sealed leak-tight to prevent infiltration of external contaminants. The cover in a traditional manhole cover assembly is lifted up and away from the frame to gain access to the infrastructure. Because manhole covers are predominantly made of iron and can weigh often...

AI Technical Summary

Benefits of technology

"The present invention is a swing-out manhole cover assembly with a ramp to make it easier to open and close the cover. The assembly includes a cover, frame, ramp, and swing assembly. The ramp helps to separate the cover from the frame when it is opened, making it easier to swing the cover out. The frame also has a support flange, frame wall, and cover support rim. The ramp is connected to the frame and the cover ramp rides up and down the frame ramp to assist with opening and closing the cover. The swing assembly includes a pivot post and the cover and frame rotate with respect to the swing assembly. The assembly also includes a spring to bias the cover in a closed position, a seal to provide a leak-tight joint between the frame and the cover, and a locking mechanism to prevent unauthorized access to the infrastructure through the manhole. The invention requires less effort and cost and is likely to operate reliably in the field."

Problems solved by technology

Because manhole covers are predominantly made of iron and can weigh often in excess of 100 pounds, the effort required to lift a manhole cover can be difficult and even injurious to the operator.

This configuration does provide assistance in lifting the manhole cover, but may not be suitable for use in pressurized applications where holes in the cover and frame are prohibited.

Also, this configuration is only suitable in locations where there is enough vertical clearance above the frame for the diameter of cover to rotate through.

This system can be more expensive than other systems because of the cost associated with the torsion springs and their installation.

Lifting an elevated cover can be more difficult than lifting a ground-level cover because typically less lifting leverage can be obtained due to the relative height of the cover to the operator.

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